KeyError(f"{name} does not exist.") while using keras tuner

Question

I am using the Keras Tuner for optimizing a CNN. I am able to get the optimal values for the filter and kernel size. But when I try to do the same for the pool size it gives me an error:

File "C:\Users\...", line 180, in pp
    -optimal learning rate for the optimizer is {best_hps.get('learning_rate')}.""")

  File "C:\Users\anaconda3\envs\venv\lib\site-packages\keras_tuner\engine\hyperparameters\hyperparameters.py", line 241, in get
    raise KeyError(f"{name} does not exist.")

KeyError: 'pool does not exist.'

My code is as follows:

 def build_model(hp):
      model = Sequential()
      model.add(Conv2D(filters=hp.Int('conv_1_filter', min_value=32, max_value=128, step=16), 
                       kernel_size=hp.Choice('conv_1_kernel', values = [2, 3,5]),
                       strides=2, 
                       input_shape=(num_rows, num_columns, num_channels), 
                       activation='relu'))
      model.add(MaxPooling2D(pool_size=hp.Choice('pool', values = [2, 3])))
  
      model.add(Flatten())

      model.add(Dense(num_labels, activation='softmax'))
  
  # Display model architecture summary 
      # model.summary()

  # Compile the model
      model.compile(loss='categorical_crossentropy', metrics=['accuracy'], optimizer=keras.optimizers.Adam(hp.Choice('learning_rate', values=[1e-2, 1e-3])))
      return model
  
  from kerastuner import RandomSearch
  tuner = RandomSearch(build_model,
                    objective='val_accuracy',
                    max_trials = 5)
  tuner.search(X_train, Y_train,epochs=3,validation_data=(X_train, Y_train),verbose = 1)
  
  # Get the optimal hyperparameters
  best_hps=tuner.get_best_hyperparameters(num_trials=1)[0]
  
  
  print(f"""The hyperparameter search is complete. The parameters are as follow:
         -optimal filter size for the first layer is {best_hps.get('conv_1_filter')}
         -optimal pool size is {best_hps.get('pool')}
         -optimal kernel size for the first layer is {best_hps.get('conv_1_kernel')}
         -optimal learning rate for the optimizer is {best_hps.get('learning_rate')}.""")

Please help me to debug this error.

Thanks!

SOLUTION:

I added overwrite=True within the keras_tuner.RandomSearch() arguments. It was taking older results and so was not showing the pool size.